1. Field of the Invention
The present invention relates to driving control of a stepping motor.
2. Description of the Related Art
Conventionally, driver circuits of stepping motors that are used in image forming apparatuses such as laser beam printers and laser facsimile machines have been commonly known (Japanese Patent Laid-Open No. 8-140398). In Japanese Patent Laid-Open No. 8-140398, vibration and noise of a motor are mitigated while securing a required level of driving performance from the motor, by causing phase currents to approximate a sinusoidal waveform.
However, according to the disclosure of Japanese Patent Laid-Open No. 8-140398, a plurality of transistors is used in order to generate phase currents having a sinusoidal waveform, and the presence of these transistors has been an obstacle to productivity improvements.
In connection with the above-described problem, it is desired to simplify a component related to switching of an excitation current in order to improve the productivity, while keeping the driving performance of a motor at a required level.